Inaugurated by IN-SPACe
ISRO Registered Space Tutor
S0-SA3-0171
What is a Time?
Grade Level:
Pre-School – Class 2
All domains without exception
Definition
What is it?
Time is how we measure when things happen and how long they last. It helps us understand the order of events, like what comes before and what comes after.
Simple Example
Quick Example
Imagine your school day. You know that assembly happens first, then classes, then lunch, and finally dismissal. This order of events, and how long each one takes, is understood using time. If your class is 45 minutes long, that's a measure of time.
Worked Example
Step-by-Step
Let's say your favourite TV show starts at 7:00 PM and lasts for 30 minutes. What time will it finish?
1. Starting time: 7:00 PM
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2. Duration of show: 30 minutes
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3. To find the finishing time, we add the duration to the starting time.
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4. Add 30 minutes to 7:00 PM.
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5. 7:00 PM + 30 minutes = 7:30 PM
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Answer: Your TV show will finish at 7:30 PM.
Why It Matters
Understanding time is crucial for everything we do, from scheduling our day to planning space missions. It's fundamental in Physics to study motion, in History to track events, and in Economics to understand market cycles. Scientists, engineers, and historians all rely on time.
Common Mistakes
MISTAKE: Confusing AM and PM, especially around noon and midnight. | CORRECTION: Remember AM is for morning (midnight to noon) and PM is for afternoon/evening (noon to midnight). 12 AM is midnight, 12 PM is noon.
MISTAKE: Adding minutes incorrectly when they go past 60 (e.g., 7:45 + 30 minutes = 7:75). | CORRECTION: When minutes reach 60 or more, convert 60 minutes into 1 hour and add it to the hour value. 7:45 + 30 minutes = 7:45 + 15 minutes + 15 minutes = 8:00 + 15 minutes = 8:15.
MISTAKE: Not understanding the difference between duration and a specific point in time. | CORRECTION: A specific point is like '3 PM'. Duration is how long something lasts, like '3 hours'.
Practice Questions
Try It Yourself
QUESTION: If your school bus arrives at 7:15 AM and the journey to school takes 20 minutes, what time do you reach school? | ANSWER: 7:35 AM
QUESTION: A train departed from Mumbai at 9:00 PM and reached Delhi after 16 hours. What time did it arrive in Delhi? (Remember AM/PM changes!) | ANSWER: 1:00 PM the next day
QUESTION: A movie starts at 6:40 PM and has an interval of 15 minutes after the first 1 hour 10 minutes. If the total movie duration is 2 hours 30 minutes, when will the movie end? | ANSWER: 9:10 PM
MCQ
Quick Quiz
Which of the following is NOT a unit of measuring time?
Second
Kilogram
Hour
Day
The Correct Answer Is:
B
Seconds, hours, and days are all units used to measure time. Kilogram is a unit for measuring mass or weight, not time.
Real World Connection
In the Real World
From checking the schedule for your favourite cricket match on TV to knowing when your online class starts, time is everywhere. Delivery apps like Swiggy and Zomato use time to tell you when your food will arrive. ISRO scientists use precise time measurements to launch rockets and satellites successfully into space.
Key Vocabulary
Key Terms
HOUR: A unit of time equal to 60 minutes. | MINUTE: A unit of time equal to 60 seconds. | SECOND: The basic unit of time. | DURATION: The length of time that something continues or lasts. | AM/PM: AM (Ante Meridiem) is before noon, PM (Post Meridiem) is after noon.
What's Next
What to Learn Next
Now that you understand what time is, you can learn about 'Units of Time' to explore different ways we measure it, like seconds, minutes, and hours. This will help you convert between different units and solve more complex problems!
